Next Article in Journal
Trends of Polychlorinated Compounds in the Surroundings of a Municipal Solid Waste Incinerator in Mataró (Catalonia, Spain): Assessing Health Risks
Previous Article in Journal
Tris(2-chloroethyl) Phosphate (TCEP) Elicits Hepatotoxicity by Activating Human Cancer Pathway Genes in HepG2 Cells
Article

Associations between Urinary, Dietary, and Water Fluoride Concentrations among Children in Mexico and Canada

1
Department of Psychology, York University, Toronto, ON M3J 1P3, Canada
2
Departamento de Salud, Universidad Iberoamericana, Ciudad de México 01219, Mexico
3
Faculty of Health Sciences, Simon Fraser University, Vancouver, BC V5A 1S6, Canada
4
School of Dentistry, Indiana University, Indianapolis, IN 46202, USA
5
Department of Social and Preventive Medicine, Laval University, Quebec City, QC G1V 0A6, Canada
6
Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
7
School of Public Health, Instituto Nacional de Salud Pública, Cuernavaca 62100, Mexico
*
Author to whom correspondence should be addressed.
Toxics 2020, 8(4), 110; https://doi.org/10.3390/toxics8040110
Received: 25 September 2020 / Revised: 29 October 2020 / Accepted: 30 October 2020 / Published: 20 November 2020
(This article belongs to the Section Toxicology)
Fluoride, which may be toxic to the developing brain, is added to salt in Mexico and drinking water in Canada to prevent dental caries. We compared childhood urinary fluoride (CUF) concentrations in Mexico City and Canada to characterize patterns of fluoride exposure in these two populations. We also examined associations of CUF with dietary and water fluoride levels in Mexico City and Canada respectively. We included 561 children (ages 4–6; mean age 4.8 years) from the Programming Research in Obesity, Growth, Environment, and Social Stress (PROGRESS) cohort in Mexico City, and 645 children (ages 2–6; mean age 3.7 years) from the Maternal–Infant Research on Environmental Chemicals (MIREC) cohort in Canada. We applied Spearman correlations, T-tests, ANOVA or covariate-adjusted linear regression to examine associations of CUF (mg/L; adjusted for specific gravity) with demographics and dietary or water fluoride concentrations. We used Welch equivalence testing to compare means across cohorts. Mean (SD) CUF was equivalent (t = 4.26, p < 0.001) in PROGRESS: 0.74 (0.42) and fluoridated Canadian communities: 0.66 (0.47), but lower in non-fluoridated Canadian communities: 0.42 (0.31) (t = −6.37, p < 0.001). Water fluoride concentrations were significantly associated with CUF after covariate adjustment for age and sex in MIREC (B = 0.44, 95% CI: 0.30, 0.59, p < 0.001). In contrast, daily food and beverage fluoride intake was not associated with CUF in PROGRESS (p = 0.82). We found that CUF levels are comparable among children in Mexico City and fluoridated Canadian communities, despite distinct sources of exposure. Community water fluoridation is a major source of fluoride exposure for Canadian children. View Full-Text
Keywords: urinary fluoride; childhood; Mexico; Canada urinary fluoride; childhood; Mexico; Canada
Show Figures

Figure 1

MDPI and ACS Style

Green, R.; Till, C.; Cantoral, A.; Lanphear, B.; Martinez-Mier, E.A.; Ayotte, P.; Wright, R.O.; Tellez-Rojo, M.M.; Malin, A.J. Associations between Urinary, Dietary, and Water Fluoride Concentrations among Children in Mexico and Canada. Toxics 2020, 8, 110. https://doi.org/10.3390/toxics8040110

AMA Style

Green R, Till C, Cantoral A, Lanphear B, Martinez-Mier EA, Ayotte P, Wright RO, Tellez-Rojo MM, Malin AJ. Associations between Urinary, Dietary, and Water Fluoride Concentrations among Children in Mexico and Canada. Toxics. 2020; 8(4):110. https://doi.org/10.3390/toxics8040110

Chicago/Turabian Style

Green, Rivka, Christine Till, Alejandra Cantoral, Bruce Lanphear, E. A. Martinez-Mier, Pierre Ayotte, Robert O. Wright, Martha M. Tellez-Rojo, and Ashley J. Malin 2020. "Associations between Urinary, Dietary, and Water Fluoride Concentrations among Children in Mexico and Canada" Toxics 8, no. 4: 110. https://doi.org/10.3390/toxics8040110

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop